1. Field of the Invention
The present invention relates to a far-infrared radiator and a method of radiating the far-infrared rays for radiating far-infrared rays in a particular wavelength range.
2. Description of the Background Art
Various kinds of heaters have conventionally been developed for heating. Especially, the sheet-like heat generating elements which use the carbon fiber (hereinafter, referred to as a carbon fiber sheet-like heat generating element) have attracted special interest recently as heat generators for radiating the far-infrared rays. The carbon fiber sheet-like heat generating elements are disclosed in Japanese Patent Publication No. 51-3098, Japanese Patent Laying-Open No. 48-101634, Japanese Patent Laying-Open No. 60-107288, Japanese Patent Laying-Open No. 60-107289, Japanese Patent Laying-Open No. 62-160681, Japanese Patent Laying-Open No. 62-281293, Japanese Patent Laying-Open No. 63-19783, Japanese Patent Laying-Open No. 1-112687, Japanese Patent Laying-Open No. 5-13151, and Japanese Patent Laying-Open No. 5- 144554, for example.
Generally, in the carbon fiber sheet-like heat generating elements, the carbon fiber is formed into a plane shape with shaping function material such as resin to stabilize the fiber structure. It is not originally desired to use flammable materials such as resin since the carbon fiber sheet-like heat generating elements generate heat to a high temperature, but those are used unavoidably as plane stabilizing materials for stabilizing the carbon fiber in plane shape. Accordingly, flammable resins are not used as the plane stabilizing material, but resins having heat resistance are selected. The main applications of such carbon fiber sheet-like heat generating elements are heating, so that developments have been widely achieved with a primary view to its heat generating characteristics and electrical characteristics.
As described above, a lot of researches have been made so far on the carbon fiber sheet-like heat generating elements in the aspect of heat generation. However, researches have been hardly made in the aspect of the far-infrared radiators. Such far-infrared radiators are used not only for heating but also used for the thermotherapy. According to the knowledge which an inventor of the present invention has acquired in his study, the far-infrared radiators can also be used for the purposes such as medical treatments which depend on wavelengths of the far-infrared rays. For that purpose, the far-infrared rays in a particular wavelength range must be selectively and efficiently radiated corresponding to the contents of the applications.
The inventor of the present invention has also acquired information that there are far-infrared ray ranges which are peculiar to individual living bodies, organs or systems, but it is not described herein because the present invention is directed to the method and the structure for radiating the far-infrared rays.